1. Field of Invention
This invention relates to free-weights used for weightlifting.
2. Description of Prior Art
This invention will allow persons (hereinafter, "weightlifters") who exercise by lifting barbells, dumbells and other weights which are not connected to chains, wires, pulleys or machines (hereinafter, "free-weights") to obtain better and more complete muscular development more quickly and efficiently.
One drawback of using free-weights is that the downward force remains constant throughout the entire exercise stroke. Because the angle, force and torque of the muscles being worked varies during the exercise stroke, there is generally a portion of the exercise stroke (the "weakpoint") through which the muscles are not able to lift as much weight as during the remaining portion of the exercise stroke (the "strongpoint"). This creates a problem as often the amount of weight weightlifters want to use through the strongpoint is too much to lift through the weakpoint, while the amount of weight the weightlifters can lift through the weakpoint is too little to sufficiently stimulate the muscles through the strongpoint.
The traditional solution is to either (1) use an amount of weight proper for the strongpoint, but stop the exercise stroke before reaching the weakpoint, or (2) perform the entire exercise stroke, but use less weight than the proper amount for the strongpoint. The problem with solution (1) is that the weightlifter is not able to exercise through the weakpoint, and therefore obtains less overall development and less or no development of any muscles that are exercised only through the weakpoint. The problem with solution (2) is that the weightlifter often must use less than the optimal weight for the strongpoint and therefore obtains less development of the muscles used through the strongpoint.
One attempt at solving the weakpoint problem has been through the use of variable resistance machines which use weights, cables, pulleys, air pressure or hydraulic. However, many weightlifters continue to use free-weights instead of machines for many reasons, including: (1) balance is developed when using free-weights, but not when using machines; (2) machines have friction generating parts which results in unwanted variation in resistance depending on the age of the machine, how well oiled it is, how tight the bolts are, etc.; (3) many weightlifters believe that free-weights develop power and strength better and more quickly than machines; (4) machines often restrict the path to be followed during an exercise motion, often to an unnatural path, resulting in less efficient muscle development, discomfort, and even injury, especially for weightlifters with very short or very long limbs; (5) many weightlifters train for contests in which free-weights are lifted, such as powerlifting or olympic weightlifting contests, and using free-weights allows them to better duplicate the contest movements; and (6) machines are usually bigger, heavier, more cumbersome, less versatile, and more expensive than free-weights.
Weightlifters would therefore benefit from an invention that would allow them to use free-weights while still properly stimulating their muscles through both the weakpoint and the strongpoint.